Paving block



F. c. SULLIVAN 2,224,582

PAVING 'BLOCK Sept. 1, 1942.

s vsheets-sheet 1 Filed NOV. 14, 1959 Fran cz's C. SuZZzvan Sept. 1,1942.

F. c. SULLIVAN PAVING BLOCK 3 Sheets-Sheet 2 Filed Nov. 14, 1939 v-|lNvENToR Francis CSuZZL'Vm Patented Sept. 1, 1942 UNITED STATES TENTOFFICE 4 Claims.

This invention `relates -to a paving block and gparticularly `to :ablock :adapted for the A,construction .of railway-crossings Variousforms `of .railway crossings have :been

,proposed heretofore .but all -of them with which =I Lam familiar are*characterized .by serious deiects. Timber floored crossings, `forexample, lack :the ldesiredduralfiilitin while Vother forms ofconstruction w-h-ich yhave longer lfif-e .are undesirable :for ionereason or another. I have .invented a novel form ,of paving block:particularly suited for the zconstruction :of railroad crossings whichentirely overcomes the objections to the cross- .ing ,floors -or paving.which have Abeen used Ahere- *.tofore.

In fthe preferred embodiment, kthe invention .comprises .fa .blockhaving a ftread .portion of wearresisting :material such .as .cast `ironanda body portion of non-metallic .materia-l -such .as concrete. Thetread and `body portions of the block Aare .secured together by .anchorvmembers embedded therein. The .blocks are of such dimensions `that theymay be .easily laid side by iside .between the rai-ls -and on theoutside of `the latter to form a ylevel pavement .presenting .a surfacewhich is highly resistant .to abrasion. ,Numerous aother novel featuresand advantages `of `the invention will be pointed out 'during the courseof the following detaileddescription which .refers to the `accompanyingdrawings illustrating `the preferred embodiment.

In the drawings- Fig. 1 :is a view partl-yin plan land 4partly in:section -on a Yplane parallel to the .tread surface;

Fig. '2 is -a Vlongitudinal section through a block, #taken :along theline I-I--I-I of Fig. 1 showing the vbloclr as installed at a crossing;vline I-I of 2 illustrates the Iplane of the -section shown 'in Fig. 1';

Fig. 3 is a transverse section through a railroad track having theblocks of my invention Vlaid I-thereon :to form alcrossing;

Fig. -4 isa transverse section through la block taken along the lineLIV-IV of Fig. 2;

Fig. '5 is 'a similar section taken Ialong the Aline V`V `of Figa:

Fig. 6 is a partial kbottom jplan Aview of ,the tread portion;

Fig. 7 is .a .partial section taken along the line VII-VII of Fig. 6;

Fig. 8 yis 'a partial section through `the tread portion before theformation of the body portion, :showing an anchor member in anintermediate rvstage; fand Fig, 9 is a section showing a portion of Fig.4 to enlarged scale.

Referring now in detail to the drawings, a paving block indicatedgenerally lat I0 comprises a tread portion II an'd a body portion I2.The tread portion is preferably of abrasionresisting material such ascast iron and has its exposed surface roughened as by the formation ofdiamonds to provide good traction. The under-surface of the treadportion II is lnot flat but is grocved longitudinally and transverselyas at I3 or otherwise shaped to provide preferred lines of fracture, fora, purpose which will appear later. A Vperipheral skirt or apron I4,extends .downwardly from the edge of the Vtread portion.

This skirt or apron tapers inwardly toward the exposed surface .of thetread portion. The tread has a longitudinal, .depending rib Ida.

The tread portion .I I may conveniently be cast in a .sand mold. Anchormembers or struts I5 preferably in the form of double, twisted lengthsof wire .are embedded in the tread portion when the latter is cast. Thegrooves I3 Yprovide a plurality of pyramidal projections I6 .on theunder-face of the tread portion and, as shown in Fig. 6, one of themembers I5 is disposed centrally of each pyramidal projection. As shownin the drawings, the eyes at the doubled ends of the anchor .members areembedded in the tread portion. vThe pattern .for .the tread portion mayconveniently be slotted to receive the anchor members during the rammingof the mold. When the mold is completed andthe pattern removed, theanchor members are .supported with their eyes exposed in the mold cavitywhereby they are embedded in the finished casting.

As shown in Figs. 8 and 9, the eyes in the anchor members I5 are large4enough to permit the molten metal to flow therethrough, thereby forminga complete linkage which resists separation of the casting and theanchor member, Even in the absence of such complete linkage, however,the tapering outline of the eye resists such separation.

The wire from which the anchor members I5 are formed is of such sizethat there is practically no fusion, burning, nor crystallizationthereof, by the heat of the molten iron during Ithe casting of the treadportion. As a matter of fact, the anchor members have the eiect of:chilling the cast iron immediately adjacent thereto, thereby providingthe latter` with a close-grained surface and insuring a tight fitbetween the tread portion and the anchor members so that the latter arerigidly supported in proper relation during subsequent manufacturingoperations.

Elongated holes I 'I are formed in the tread portion Il near each endthereof adapted to receive suitable lifting tools. Necks I8' dependingbelow the tread portion around the holes il have notches I9 formedtherein at right angles to the longer dimension of the holes I'I. Thenotches I9 are adapted to be engaged by the T-head of a lifting tool 29when inserted through the holes I'I and turned 90.

When the tread portion has been cast with the eyes of the anchor membersI embedded therein, the ends of the latter are twisted by any suitablemeans to form a shank 2|, the eX- treme ends being left open as at 22 toprovide a chair for supporting reinforcing bars 23 adapted to beembedded in the body portion I2. The bars 23 are laid in the chairs andthe open ends of the latter bent around the bars as shown in Fig. 9 andhammered down. The assembled tread portion, anchor members andreinforcing bars thus constitute a rigid assembly. The latter isdeposited in a suitable mold with the tread portion Il down and concreteor the like is poured in the mold to form the body portion I2.

The struts I5 are spaced apart along the bars 23 by a distance less thanthe length of the struts and form a grid between the bars and treadportion which, with the concrete between the struts, constitutes a trussresisting any bending stress applied to the tread portion.

After the concrete has been poured into the mold, bearing plates 24 areembedded in each end of the block. The plates are preferably of castiron, are L-shaped in section, and extend the full Width of the blocks.They are provided with integral chairs 25 forming seats for engaging thereinforcing bars. The inner horizontal surface of the plates may havepyramidal projections thereon, similar to those on the under surface ofthe tread plate, and may also have embedded therein wire anchors similarto those shown at l5, and secured to the reinforcing bars.

Holes 26 in alinement with the holes I'I are formed in the body portionby suitable cores. The sides of the body portion taper inwardly towardthe bottom. The concrete of which the body portion is formed makes atight bond with the under-surface of the tread portion, the bearingplates, the anchor members I5 and the bars 23 so that, to all intentsand purposes, the resulting block is a unitary member.

The blocks Ill preferably have a length equal to twice the standardcenter-to-center spacing of railroad ties and a width such that three ofthe blocks disposed side by side fill up the desired portion of thespace between the rails as shown in Fig. 3. The depth of the blocks asalso shown in Fig. 3, is approximately equal to the height of the railabove the fiange thereof.

In constructing a crossing floor or pavement, the blocks I@ are laidlongitudinally on the track with their ends resting on spacers 27 placedon the ties or sleepers. Wooden spacers 28 and 2S are disposed on eachside of the rails indicated at 3d. The blocks are quite heavy, e. g.,approximately 590 lbs., to prevent bouncing under the.

action of car wheels traversing the track. The blocks may beconveniently handled nevertheless by four men using two of the liftingtools 29. When properly placed, the blocks do not require any attachmentto the track or ties, remaining in proper position thereon merely byvirtue of their own weight. In laying the blocks on the ties, the endjoints need not be staggered.

The upward taper of the skirt III provides grooves between adjacentblocks which may be filled with sealing material 3l to prevent seepageof water through the joints. The downward taper on the body portion I2facilitates the removal of any block, if desirable for any purpose, asWell as the original setting of the blocks on the ties.

The plates 24 as shown in Fig. 2, bear on the spacer blocks 2l restingon alternate ties, and provide durable support-engaging surfaces.

' The block of my invention is characterized by numerous advantages overanything known heretofore. In the first place, the blocks are providedwith an all-metal tread surface having a uniformly high resistance toabrasion. The blocks are unitary, for all practical purposes. Because ofthe rm anchorage of the members I5 in the tread portion Il and theirattachment to the reinforcing bars 23, the body and tread portions arefirmly bound together. Since one of the members I5 is embedded in eachof the projections I6, breakage of the tread portion along the lines ofgrooves I3 would not permit the chipping out of fragments of the treadportion. Any breakage would follow the lines of the grooves I3 and evenif cracks appeared along all such grooves, each separate fragment of thetread portion would be securely anchored to the body portion. The holesI1 and 26 permit circulation of air through the ballast in which theties are laid to assist in drying it out. They also provide air ventsduring the vibration of the entire track under the car Wheels, therebypreventing the sucking-up of soil particles through the crevices betweenthe ballast rock, and the resulting obstruction to drainage of thelatter, as has been experienced with plastic materials laid in acontinuous layer to provide a crossing floor or pavement. The blocks caneasily be designed to have the desired strength when loaded as a beamsupported at the ends of the span between alternate ties and may also bedesigned to have the weight necessary to hold it in proper position. Theblocks are of such character, furthermore, that they may be manufacturedat relatively low cost. They are practically indestructible underordinary conditions and their durability, therefore, is almostunlimited. Since each block rests on only two ties, it is not necessarythat the three ties covered by the length of each block be accuratelyleveled.

Although I have illustrated and described but a preferred embodiment ofthe invention, it Will be recognized that changes in the details of theconstruction disclosed may be made without departing from the spirit ofthe invention or the scope of the appended claims.

I claim:

1. A paving block comprising a metal tread portion and a non-metallicbody portion, the lower surface of the tread portion having amultiplicity of pyramidal projections, and an anchor embedded in eachpyramidal projection and eX- tending downwardly into the body portion,whereby any fracture of the tread Will follow the grooves betweenpyramidal sections, leaving all fragments firmly secured to the bodyporion.

2. A block adapted for use in railroad crossings or the like, comprisinga cast metal tread portion and a non-metallic body portion, the top ofthe tread portion being roughened to provide good traction and thebottom of said tread portion having projections which together defineintersecting grooves to provide preferred lines of fracture, reinforcingbars embedded in said body portion, and ties each having one endembedded in one of said projections and the other end secured to one ofsaid bars.

3. A paving block adapted for use in railroad crossings or the like,comprising a cast metal tread portion, a non-metallic, reinforced bodyportion, Wire struts having one end embedded in said tread portion andthe other end secured to the reinforcement in said body portion, thebottom of the tread portion having a plurality of lpyramidalprojections, the sides of the bases of adjacent projections being alinedand close together, said struts extending into the tread portionsubstantially through the apices of said projections.

4. A paving block particularly adapted for use on railroad crossingscomprising a non-metallic body portion adapted to be supported onsleepers or the like, and a metallic tread portion bonded to said bodyportion, said body portion having horizontal metal reinforcing barsembedded therein adjacent the bottom thereof, and a plurality of strutsalso embedded in said body portion, said struts extending verticallybetween the bars and tread portion, secured to the bars and embedded inthe tread portion, and spaced apart along the bars by a distance notgreater than their length, thereby forming a grid connecting the treadportion to said bars and constituting, with the `material of the bodyportion therebetween, a truss resisting bending stress applied to saidtread portion.

FRANCIS CL SULLIVAN.

